Multi-press support

[ickshonpe]

Objective

The text input widget selects the word under the pointer on a double click. This isn't correct, the select word edit should be queued on the press following a click. This allows for users to select a word with a double press and then hold the button and drag to extend the selection.

Solution

Track multi-presses as well as multi-clicks:

• Add a count field to Press events.
• Update the click count in PointerButtonState::clicking on consecutive presses within the multi-click duration, not on releases.
• Filter the clicking map in both the Press and Click dispatchers.
• Removed the MULTI_CLICK_DURATION const.
• The multi-click duration can now be set using a new multi_click_duration field on the PickingSettings resource.

Testing

cargo run --example multiline_text_input

You should observe that dragging after selecting a word with a double press extends the selection.

[nicoburns]

It's still not quite right as the selection is extended from the point in the word that was clicked, not the word itself. That's not something we can fix here (I think), it needs Parley to special case drag selects after word selection.

Pretty sure Parley's vello_editor example implements this, so it ought to be possible to do here.

[ickshonpe]

Pretty sure Parley's vello_editor example implements this, so it ought to be possible to do here.

Yep you are right. It was the bug fixed by #24260 collapsing the selection before the drag with an extra move_to_point call. Merged with main, and it works correctly now.

[github-actions]

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[jordanhalase]

A great QoL improvement.

Something I've noticed when testing: Clicking on one word and then quickly clicking on a different word will select that whole word. Multi-press counter should be restarted when the cursor moves beyond a few pixels delta.

We could iterate though.

[ickshonpe]

A great QoL improvement.

Something I've noticed when testing: Clicking on one word and then quickly clicking on a different word will select that whole word. Multi-press counter should be restarted when the cursor moves beyond a few pixels delta.

We could iterate though.

Yeah I deliberately ignored distance in the click PR and this one because I didn't want to bother with it because there might be some annoying scaling problems. I guess though maybe thinking about it now, we could just keep the timing in the picking module and then compare the distance in the widget logic. Then we could even have an explicit check that both presses are on the same word.

[ickshonpe]

There's no need for a migration guide I think, there aren't any breaking changes.